Pneumatic cushion.



(I. HOPMANN.

PNEUMATIG CUSHION. APLIGATON FILED SEPT.6,1911. @$39,552,271 Patented. Sapt. 24, i912.

2 SHEETS-SHEET l.

.TSEF HOFIVIANN, OF BUMARGOHE, SVITZERLAND.

jppleaton filed September `6 19?..1..

luv

re'terence inarled thereon. which torni' a part ot this specification.

invention relates iieuinatic for vehicles. more ially for chicles. in which a pneumatic diaarranged Within a rigid recepor easing and coiugeratinwith a plun err (ko ln pneumatic cushione hitherto in the Size. il the opening of the casing which is closed by die dialiihrag'ni and plunger remains constant during the u'hole stroke ot the plunger.

Bj." applying' steel springs Within the caeingr the smoothness of .the resiliency which eepecially ot advantage pneumatic euehione is diminished. Coinpreesion of the air on the other hand resulta and produces; heat that damages the inatcrial oi' the diaphragin. Another drawback of these pneumatic cushions the unfavorable stress en the material of the diaphragm caused by the diaphrannrbecoming folded or creased.

One objecty of the present invention is to so construct the Spring or cushion. that there 'takes' place froni'the neutral position of the same a continual increase of the ellective diameter ol' the receptacle which is closed by the diaphragm and i the plunge and thereby increasing' the ellective pneumatic pressure on the piston nieniber or plunger.

A eonstructnni according to this invention ie illustrated by Way of example in the accompanying drawing in Which- Figure 1 ie a longitudinal section through the nneuinatic cushion. llig. 2 iena longil i on on line B-l of FilL 1. Fig. il illuetra'tee the Working* o;'` the device. ig.

ehous the saule mounted on a vehicle.

linder ine-.miller or casing 1 of rigid. material is `nrjiunted on the trainelS .of a.

Specicaton of 'Letters latent.

.which is secured a The casing l) Cong'gs atented SepaQf-., i912?. Serial No. 647,945.

of two parte oidifferent diameters which are connected to each other by a conical rrai-t. making the bestuse ot the available Space between the frame and the .vheels` of the cai', the casing; 1 Will preferably be oblong; erase-section will be Seen from Fig. Q. To the lower part of the casing` 1 ie secured ,a box 2 with a lining which forms a guide for a tube Al5. A piston ineinber or plunger 5 being,` screwed to the upper end of the tube 4 is essentially of conical shape, rounded oil on the top and provided. inside with a spherical recess G Yforming a. bearing` for the upper spherical journal of a Supporting` red 7. The lower spherical journal of the rod is `anita-bly supported by a plate S :secured 'to the axle 9 of the vehicle or otherwise. rEhe upper end of the casing 'i is provided with a flange 11 to vvaulted cover 13 by means of bolts 12.

The edge of a pneumatic diaphragm 14 is' held tight between the flanges of the casing l and the cover 13. The diapl ragni 14. inay consist of any YSuitable material layof fabric alternatingy with layers of rubber for instance. The diaphragm partly reste against the inner Wall of casing" 1 and partly against the plunger ,fr pin 16 le vulcanized to the diaphragm 141 and engages a notch providedatthe Atop ot' the plunger-5, whereby sliding oi: the diaphragm on the plunger is prevented.

fr completely' air-tight chamber A ie formed by the above described arrangement. rihis chamber iS illetl ivith air and is con- '.nected to an air chamber 19 bv a Dive 15;

A pneumatic spring` as described above 1S provided at every wheel ot the vehicle.

Any suitable number ofair-chamhere inay l be applied, one air chamber may be provided for every spring or for every axle, or all springs may be connected to one and the Same air chamber 'for instance.

r-llhe device acts ae follower A pressure exerted from below on Ythe axle 9 causes the plunger 5 to enten'eolnewlnit more into the chamber A. lie-relay a part of the diaphragm l-lis taken lfrom lagainst the casing 1 and put against the plunger 5. 1n so doing, .the ei'ieetive area of the movable parte, pieton and diaphraginwis increased,

that the total preseur i inthe piston increases as the pieten rieee .the casing The be?, e piston member in the cylinder member chamber, and means to connect the air space-'10i am'anged to move on'gitudinally in either in the cylinder member with said chamber. direction from its normal position, a dia- In testimony thatv I claim the foregoing phmgm between the two members, said as my invention, I have signed my name in members having diaphragmsup orting presence of two .subscrib' witnesses.

weils (livel-ging fi-om each other t at in- JOSE HOFMANN.- eiease 'the effective areay of `the piston and Witnesses: diaphragm as the piston member enters .the ALFRED Coos,

cylinder member and j vice verse, an air CARL GUBLER. 

